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Analytical and Bioanalytical Chemistry Mar 2022Peroxisomes are versatile single membrane-enclosed cytoplasmic organelles, involved in reactive oxygen species (ROS) and lipid metabolism and diverse other metabolic...
Peroxisomes are versatile single membrane-enclosed cytoplasmic organelles, involved in reactive oxygen species (ROS) and lipid metabolism and diverse other metabolic processes. Peroxisomal disorders result from mutations in Pex genes-encoded proteins named peroxins (PEX proteins) and single peroxisomal enzyme deficiencies. The PEX11 protein family (α, β, and γ isoforms) plays an important role in peroxisomal proliferation and fission. However, their specific functions and the metabolic impact caused by their deficiencies have not been precisely characterized. To understand the systemic molecular alterations caused by peroxisomal defects, here we utilized untreated peroxisomal biogenesis factor 11α knockout (Pex11α KO) mouse model and performed serial relative-quantitative lipidomic, metabolomic, and proteomic analyses of serum, liver, and heart tissue homogenates. We demonstrated significant specific changes in the abundances of multiple lipid species, polar metabolites, and proteins and dysregulated metabolic pathways in distinct biological specimens of the Pex11α KO adult mice in comparison to the wild type (WT) controls. Overall, the present study reports comprehensive semi-quantitative molecular omics information of the Pex11α KO mice, which might serve in the future as a reference for a better understanding of the roles of Pex11α and underlying pathophysiological mechanisms of peroxisomal biogenesis disorders.
Topics: Animals; Lipidomics; Liver; Membrane Proteins; Mice; Mice, Knockout; Proteomics
PubMed: 35083512
DOI: 10.1007/s00216-021-03860-0 -
Biomolecules Jul 2021Premature termination codon (PTC) mutations account for approximately 10% of pathogenic variants in monogenic diseases. Stimulation of translational readthrough, also...
Premature termination codon (PTC) mutations account for approximately 10% of pathogenic variants in monogenic diseases. Stimulation of translational readthrough, also known as stop codon suppression, using translational readthrough-inducing drugs (TRIDs) may serve as a possible therapeutic strategy for the treatment of genetic PTC diseases. One important parameter governing readthrough is the stop codon context (SCC)-the stop codon itself and the nucleotides in the vicinity of the stop codon on the mRNA. However, the quantitative influence of the SCC on treatment outcome and on appropriate drug concentrations are largely unknown. Here, we analyze the readthrough-stimulatory effect of various readthrough-inducing drugs on the SCCs of five common premature termination codon mutations of in a sensitive dual reporter system. Mutations in , encoding the peroxisomal targeting signal 1 receptor, can cause peroxisomal biogenesis disorders of the Zellweger spectrum. We show that the stop context has a strong influence on the levels of readthrough stimulation and impacts the choice of the most effective drug and its concentration. These results highlight potential advantages and the personalized medicine nature of an SCC-based strategy in the therapy of rare diseases.
Topics: Codon, Nonsense; HeLa Cells; Humans; Peroxisomal Disorders; Peroxisome-Targeting Signal 1 Receptor; Protein Biosynthesis; RNA, Messenger
PubMed: 34356630
DOI: 10.3390/biom11071006 -
Journal of Child Neurology Apr 2022Cerebral X-linked adrenoleukodystrophy (cALD) is an inflammatory demyelination of the brain that can lead to death unless treated by hematopoietic stem cell...
OBJECTIVES
Cerebral X-linked adrenoleukodystrophy (cALD) is an inflammatory demyelination of the brain that can lead to death unless treated by hematopoietic stem cell transplantation. Survival and improved outcomes for cerebral adrenoleukodystrophy are associated with hematopoietic stem cell transplantation at earliest evidence of disease on magnetic resonance imaging (MRI). Our goal was to determine average duration between diagnosis of cALD and hematopoietic stem cell transplantation.
METHODS
This was a retrospective review of data of patients aged 18 years or younger, using a nationwide administrative health care database (Pediatric Health Information System), with an () diagnosis of adrenoleukodystrophy. Time range was October 1, 2015, through June 30, 2021. We determined time to hematopoietic stem cell transplantation by duration between index brain MRI and a code for hematopoietic stem cell transplantation.
RESULTS
We identified 27 patients with cerebral adrenoleukodystrophy. Total charges for the cohort was $53 million. Time to transplant averaged 97 days. For Hispanic patients, time to transplant was 117 days, compared with 80 days for White, non-Hispanic patients. Comparison of different hospitals showed significant variability in time to hematopoietic stem cell transplantation.
DISCUSSION
We found that time to hematopoietic stem cell transplantation was >3 months for patients with cerebral adrenoleukodystrophy in the hospitals we evaluated. We noted differences in average time by race/ethnicity and by hospital. Our findings suggest opportunity to reduce time to transplant in cerebral adrenoleukodystrophy.
Topics: Adrenoleukodystrophy; Child; Hematopoietic Stem Cell Transplantation; Humans; Magnetic Resonance Imaging; Retrospective Studies
PubMed: 35238239
DOI: 10.1177/08830738221081141 -
BMJ Case Reports Apr 2022Hyperimmunoglobulinaemia D syndrome (HIDS) is a rare autosomal recessive disorder caused by mutations in the mevalonate kinase (MVK) gene, located on chromosome 12. The...
Hyperimmunoglobulinaemia D syndrome (HIDS) is a rare autosomal recessive disorder caused by mutations in the mevalonate kinase (MVK) gene, located on chromosome 12. The most common mutation identified in MVK gene so far is V377I. Compound heterozygotes that include this variant may exhibit a more severe phenotype of the disease and homozygotes are rarely found in clinical practice probably they express a milder phenotype. HIDS is a chronic autoinflammatory disease characterised by recurrent febrile episodes, associated with lymphadenopathies, abdominal pain, rash and arthritis. These flares can be triggered by vaccination, minor trauma, surgery and stress.We report a case of a 2-year-old girl who had recurrent attacks of fever associated with cervical lymphadenopathy, macular erythematous skin rash, abdominal pain and aphthous ulcers in the mouth. The patient was found to excrete elevated amounts of urinary mevalonic acid and a homozygous V337I mutation in the MVK gene was identified.
Topics: Abdominal Pain; Child, Preschool; Female; Fever; Homozygote; Humans; Immunoglobulin D; Mevalonate Kinase Deficiency; Mutation; Phosphotransferases (Alcohol Group Acceptor)
PubMed: 35387795
DOI: 10.1136/bcr-2022-249135 -
British Journal of Clinical Pharmacology Jun 2022X-linked adrenoleukodystrophy (X-ALD) is an inherited, neurodegenerative rare disease that can result in devastating symptoms of blindness, gait disturbances and spastic... (Review)
Review
X-linked adrenoleukodystrophy (X-ALD) is an inherited, neurodegenerative rare disease that can result in devastating symptoms of blindness, gait disturbances and spastic quadriparesis due to progressive demyelination. Typically, the disease progresses rapidly, causing death within the first decade of life. With limited treatments available, efforts to determine an effective therapy that can alter disease progression or mitigate symptoms have been undertaken for many years, particularly through drug repurposing. Repurposing has generally been guided through clinical experience and small trials. At this time, none of the drug candidates have been approved for use, which may be due, in part, to the lack of pharmacokinetic/pharmacodynamic information on the repurposed medications in the target patient population. Greater consideration for the disease pathophysiology, drug pharmacology and potential drug-target interactions, specifically at the site of action, would improve drug repurposing and facilitate drug development. Incorporating advanced translational and clinical pharmacological approaches in preclinical studies and early-stage clinical trials will improve the success of repurposed drugs for X-ALD as well as other rare diseases.
Topics: Adrenoleukodystrophy; Disease Progression; Drug Repositioning; Humans; Pharmacology, Clinical; Rare Diseases
PubMed: 34558098
DOI: 10.1111/bcp.15090 -
Medicina 2020Inherited metabolism disorders are serious childhood diseases that lead to significant cognitive impairment and regression of psychomotor development. The... (Review)
Review
Inherited metabolism disorders are serious childhood diseases that lead to significant cognitive impairment and regression of psychomotor development. The pathophysiology of the neural progressive deterioration is usually associated with severe neuroinflammation and demyelination, and as a consequence, neurodegeneration. At the moment they have no adequate treatment and require early and aggressive therapeutic approaches, which entail high mortality rates and, very frequently, low degrees of functional improvement and survival. Bone marrow transplantation and bone marrow mesenchymal cells grafts are therapeutic and experimental therapies that improve the course of these diseases through different mechanisms of action: enzyme replacement, membrane exchange and regulation of the inflammatory process.
Topics: Bone Marrow Transplantation; Humans; Lysosomal Storage Diseases; Mesenchymal Stem Cell Transplantation; Peroxisomal Disorders
PubMed: 32150704
DOI: No ID Found -
Orphanet Journal of Rare Diseases May 2023The peroxisome is a ubiquitous single membrane-enclosed organelle with an important metabolic role. Peroxisomal disorders represent a class of medical conditions caused...
Multivariate analysis and model building for classifying patients in the peroxisomal disorders X-linked adrenoleukodystrophy and Zellweger syndrome in Chinese pediatric patients.
BACKGROUND
The peroxisome is a ubiquitous single membrane-enclosed organelle with an important metabolic role. Peroxisomal disorders represent a class of medical conditions caused by deficiencies in peroxisome function and are segmented into enzyme-and-transporter defects (defects in single peroxisomal proteins) and peroxisome biogenesis disorders (defects in the peroxin proteins, critical for normal peroxisome assembly and biogenesis). In this study, we employed multivariate supervised and non-supervised statistical methods and utilized mass spectrometry data of neurological patients, peroxisomal disorder patients (X-linked adrenoleukodystrophy and Zellweger syndrome), and healthy controls to analyze the role of common metabolites in peroxisomal disorders, to develop and refine a classification models of X-linked adrenoleukodystrophy and Zellweger syndrome, and to explore analytes with utility in rapid screening and diagnostics.
RESULTS
T-SNE, PCA, and (sparse) PLS-DA, operated on mass spectrometry data of patients and healthy controls were utilized in this study. The performance of exploratory PLS-DA models was assessed to determine a suitable number of latent components and variables to retain for sparse PLS-DA models. Reduced-features (sparse) PLS-DA models achieved excellent classification performance of X-linked adrenoleukodystrophy and Zellweger syndrome patients.
CONCLUSIONS
Our study demonstrated metabolic differences between healthy controls, neurological patients, and peroxisomal disorder (X-linked adrenoleukodystrophy and Zellweger syndrome) patients, refined classification models and showed the potential utility of hexacosanoylcarnitine (C26:0-carnitine) as a screening analyte for Chinese patients in the context of a multivariate discriminant model predictive of peroxisomal disorders.
Topics: Child; Humans; Adrenoleukodystrophy; East Asian People; Multivariate Analysis; Peroxisomal Disorders; Zellweger Syndrome; China
PubMed: 37189159
DOI: 10.1186/s13023-023-02673-x -
International Journal of Molecular... Aug 2019Peroxisome biogenesis disorders (PBDs) are nontreatable hereditary diseases with a broad range of severity. Approximately 65% of patients are affected by mutations in... (Review)
Review
Peroxisome biogenesis disorders (PBDs) are nontreatable hereditary diseases with a broad range of severity. Approximately 65% of patients are affected by mutations in the peroxins Pex1 and Pex6. The proteins form the heteromeric Pex1/Pex6 complex, which is important for protein import into peroxisomes. To date, no structural data are available for this AAA+ ATPase complex. However, a wealth of information can be transferred from low-resolution structures of the yeast Pex1/Pex6 complex and homologous, well-characterized AAA+ ATPases. We review the abundant records of missense mutations described in PBD patients with the aim to classify and rationalize them by mapping them onto a homology model of the human Pex1/Pex6 complex. Several mutations concern functionally conserved residues that are implied in ATP hydrolysis and substrate processing. Contrary to fold destabilizing mutations, patients suffering from function-impairing mutations may not benefit from stabilizing agents, which have been reported as potential therapeutics for PBD patients.
Topics: ATPases Associated with Diverse Cellular Activities; Adenosine Triphosphate; Amino Acid Sequence; Animals; Humans; Membrane Proteins; Models, Molecular; Mutation, Missense; Peroxisomal Disorders; Protein Conformation; Protein Interaction Maps; Sequence Alignment
PubMed: 31374812
DOI: 10.3390/ijms20153756 -
Aging Mar 2020Peroxisomes are small, membrane-enclosed eukaryotic organelles that house various enzymes with metabolic functions. One important feature in both Hutchinson-Gilford...
Peroxisomes are small, membrane-enclosed eukaryotic organelles that house various enzymes with metabolic functions. One important feature in both Hutchinson-Gilford Progeria Syndrome (HGPS) and normal aging is the elevated levels of Reactive Oxygen Species (ROS), which are generated from metabolic pathways with the capacity to cause oxidative damage to macromolecules within the cells. Although peroxisomal bioreactions can generate free radicals as their byproducts, many metabolic enzymes within the peroxisomes play critical roles as ROS scavengers, in particular, catalase. Here, we observed impaired peroxisomes-targeting protein trafficking, which suggested that the poorly assembled peroxisomes might cause high oxidative stress, contributing to the premature senescent phenotype in HGPS. We then investigated the ROS clearance efficiency by peroxisomal enzymes and found a significantly decreased expression of catalase in HGPS. Furthermore, we evaluated the effects of two promising HGPS-treatment drugs Methylene Blue and RAD001 (Everolimus, a rapamycin analog) on catalase in HGPS fibroblasts. We found that both drugs effectively reduced cellular ROS levels. MB, as a well-known antioxidant, did not affect catalase expression or activity. Interestingly, RAD001 treatment significantly upregulated catalase activity in HGPS cells. Our study presents the first characterization of peroxisomal function in HGPS and provides new insights into the cellular aspects of HGPS and the ongoing clinical trial.
Topics: Acatalasia; Cell Line; Cellular Senescence; Enzyme Inhibitors; Everolimus; Fibroblasts; Humans; Lamin Type A; Methylene Blue; Mutation; Peroxisomes; Phenotype; Progeria; Reactive Oxygen Species
PubMed: 32186522
DOI: 10.18632/aging.102941 -
Annals of Clinical and Translational... May 2020To identify a pharmacological compound targeting macrophages, the most affected immune cells in inflammatory X-linked adrenoleukodystrophy (cerebral X-ALD) caused by... (Comparative Study)
Comparative Study
OBJECTIVE
To identify a pharmacological compound targeting macrophages, the most affected immune cells in inflammatory X-linked adrenoleukodystrophy (cerebral X-ALD) caused by ABCD1 mutations and involved in the success of hematopoietic stem cell transplantation and gene therapy.
METHODS
A comparative database analysis elucidated the epigenetic repressing mechanism of the related ABCD2 gene in macrophages and identified the histone deacetylase (HDAC) inhibitor Vorinostat as a compound to induce ABCD2 in these cells to compensate for ABCD1 deficiency. In these cells, we investigated ABCD2 and pro-inflammatory gene expression, restoration of defective peroxisomal β-oxidation activity, accumulation of very long-chain fatty acids (VLCFAs) and their differentiation status. We investigated ABCD2 and pro-inflammatory gene expression, restoration of defective peroxisomal ß-oxidation activity, accumulation of very long-chain fatty acids (VLCFA) and differentiation status. Three advanced cerebral X-ALD patients received Vorinostat and CSF and MRI diagnostics was carried out in one patient after 80 days of treatment.
RESULTS
Vorinostat improved the metabolic defects in X-ALD macrophages by stimulating ABCD2 expression, peroxisomal ß-oxidation, and ameliorating VLCFA accumulation. Vorinostat interfered with pro-inflammatory skewing of X-ALD macrophages by correcting IL12B expression and further reducing monocyte differentiation. Vorinostat normalized the albumin and immunoglobulin CSF-serum ratios, but not gadolinium enhancement upon 80 days of treatment.
INTERPRETATION
The beneficial effects of HDAC inhibitors on macrophages in X-ALD and the improvement of the blood-CSF/blood-brain barrier are encouraging for future investigations. In contrast with Vorinostat, less toxic macrophage-specific HDAC inhibitors might improve also the clinical state of X-ALD patients with advanced inflammatory demyelination.
Topics: ATP Binding Cassette Transporter, Subfamily D; ATP Binding Cassette Transporter, Subfamily D, Member 1; Acute Disease; Adrenoleukodystrophy; Coenzyme A Ligases; Histone Deacetylase Inhibitors; Humans; Inflammation; Macrophages; Magnetic Resonance Imaging; Outcome Assessment, Health Care; Peroxisomes; Vorinostat
PubMed: 32359032
DOI: 10.1002/acn3.51015